Started to refactor the object structure

common.nim

@@ -18,28 +18,26 @@ import strutils
 import meta/valueobject
 import meta/tokenobject
 import types/objecttype
-import types/functiontype
-import types/stringtype
 
 
 const FRAMES_MAX* = 400  # TODO: Inspect why the VM crashes if this exceeds 400
 const JAPL_VERSION* = "0.2.0"
 const JAPL_RELEASE* = "alpha"
-const DEBUG_TRACE_VM* = false
-const DEBUG_TRACE_GC* = true
-const DEBUG_TRACE_ALLOCATION* = true
-const DEBUG_TRACE_COMPILER* = true
+const DEBUG_TRACE_VM* = true   # Traces VM execution
+const DEBUG_TRACE_GC* = true    # Traces the garbage collector (TODO)
+const DEBUG_TRACE_ALLOCATION* = true   # Traces memory allocation/deallocation (WIP)
+const DEBUG_TRACE_COMPILER* = true   # Traces the compiler (TODO)
 
 
 type
-    CallFrame* = ref object
+    CallFrame* = ref object    # FIXME: Call frames are broken (end indexes are likely wrong)
         function*: ptr Function
         ip*: int
         slot*: int
         endSlot*: int
         stack*: seq[Value]
 
-    VM* = ref object
+    VM* = ref object    # The VM object
         lastPop*: Value
         frameCount*: int
         source*: string
@@ -50,12 +48,12 @@ type
         globals*: Table[string, Value]
         file*: string
 
-    Local* = ref object
+    Local* = ref object   # A local variable
        name*: Token
        depth*: int
 
 
-    Parser* = ref object
+    Parser* = ref object  # A Parser object
         current*: int
         tokens*: seq[Token]
         hadError*: bool
@@ -68,7 +66,7 @@ proc getView*(self: CallFrame): seq[Value] =
 
 
 proc getAbsIndex(self: CallFrame, idx: int): int =
-    return idx + len(self.getView()) - 1   # Inspect this code (locals, functions)
+    return idx + len(self.getView()) - 1   # TODO: Inspect this code (locals, functions)
 
 
 proc len*(self: CallFrame): int =
@@ -117,6 +115,8 @@ func stringify*(value: Value): string =
             result = "-inf"
 
 
+## TODO: Move this stuff back to their respective module
+
 proc initParser*(tokens: seq[Token], file: string): Parser =
     result = Parser(current: 0, tokens: tokens, hadError: false, panicMode: false, file: file)
 
@@ -128,6 +128,7 @@ proc hashFloat(f: float): uint32 =
     result *= 16777619
 
 
+# TODO: Move this into an hash() method for objects
 proc hash*(value: Value): uint32 =
     case value.kind:
         of INTEGER:
@@ -149,6 +150,7 @@ proc hash*(value: Value): uint32 =
             result = uint32 0
 
 
+# TODO: Move this into a bool() method for objects
 func isFalsey*(value: Value): bool =
     case value.kind:
         of BOOL:
@@ -173,6 +175,7 @@ func isFalsey*(value: Value): bool =
             result = true
 
 
+# TODO: Move this to a toString() method for objects
 func typeName*(value: Value): string =
     case value.kind:
         of ValueType.Bool, ValueType.Nil, ValueType.Double,
@@ -189,7 +192,7 @@ func typeName*(value: Value): string =
                 else:
                     result = value.obj.typeName()
 
-
+# TODO: Move this to a eq() method for objects
 proc valuesEqual*(a: Value, b: Value): bool =
     if a.kind != b.kind:
         result = false

types/exceptions.nim

@@ -21,11 +21,6 @@ import strformat
 import ../memory
 
 
-type JAPLException* = object of Obj
-    errName*: ptr String
-    message*: ptr String
-
-
 proc stringify*(self: ptr JAPLException): string =
     return &"{self.errName.stringify}: {self.message.stringify}"
 

types/functiontype.nim

@@ -29,12 +29,6 @@ import tables
 
 
 type
-    Function* = object of Obj
-        name*: ptr String
-        arity*: int
-        optionals*: int
-        defaults*: Table[string, Value]
-        chunk*: Chunk
     FunctionType* = enum
         FUNC, SCRIPT
 

types/objecttype.nim

@@ -15,6 +15,8 @@
 ## Base structure for objects in JAPL, all
 ## types inherit from this simple structure
 
+import tables
+
 
 type
     ObjectType* {.pure.} = enum
@@ -25,9 +27,41 @@ type
     Obj* = object of RootObj
         kind*: ObjectType
         hashValue*: uint32
+    String* = object of Obj    # A string object
+        str*: ptr UncheckedArray[char]  # TODO -> Unicode support
+        len*: int
+    Function* = object of Obj
+        name*: ptr String
+        arity*: int
+        optionals*: int
+        defaults*: Table[string, Value]
+        chunk*: Chunk
+    JAPLException* = object of Obj
+        errName*: ptr String
+        message*: ptr String
 
 
-func objType*(obj: ptr Obj): ObjectType =
+
+
+
+# Maps enum types to actual JAPL object types
+const objectMapping = to_table({
+                               String: Obj,  # TODO
+                               Exception: Obj,
+                               Function: Obj,
+                               Class: Obj,
+                               Module: Obj
+                               })
+
+
+template `convert`(a: ptr Obj): untyped =
+    ## Performs conversions from a JAPL
+    ## supertype to a subtype
+
+    cast[ptr objectMapping[a.kind]](a)
+
+
+proc objType*(obj: ptr Obj): ObjectType =
     ## Returns the type of the object
     return obj.kind
 

types/stringtype.nim

@@ -22,11 +22,6 @@ import strformat
 import ../memory
 
 
-type String* = object of Obj
-    str*: ptr UncheckedArray[char]  # TODO -> Maybe ptr UncheckedArray[array[4, char]]?
-    len*: int
-
-
 proc stringify*(s: ptr String): string =
     result = ""
     for i in 0..<s.len:

vm.nim

@@ -583,8 +583,8 @@ proc run(self: var VM, repl: bool): InterpretResult =
             of OpCode.Return:
                 var retResult = self.pop()
                 if repl:
-                    if not self.lastPop.isNil() and self.frameCount == 1:   # This is to avoid long outputs
-                        # with recursive calls
+                    if not self.lastPop.isNil() and self.frameCount == 1:   # This is to avoid
+                        # useless output with recursive calls
                         echo stringify(self.lastPop)
                         self.lastPop = Value(kind: ValueType.Nil) # TODO: asNil()?
                 self.frameCount -= 1
@@ -604,13 +604,13 @@ proc freeObject(obj: ptr Obj) =
         of ObjectType.Function:
             var fun = cast[ptr Function](obj)
             when DEBUG_TRACE_ALLOCATION:
-                echo &"Freeing function object with value '{stringify(fun)}'"
+                echo &"DEBUG: Freeing function object with value '{stringify(fun)}'"
             fun.chunk.freeChunk()
             discard free(ObjectType.Function, fun)
         of ObjectType.String:
             var str = cast[ptr String](obj)
             when DEBUG_TRACE_ALLOCATION:
-                echo &"Freeing string object with value '{stringify(str)}' of length {str.len}"
+                echo &"DEBUG: Freeing string object with value '{stringify(str)}' of length {str.len}"
             discard freeArray(char, str.str, str.len)
             discard free(ObjectType.String, obj)
         else:
@@ -625,13 +625,13 @@ proc freeObjects(self: var VM) =
         freeObject(obj)
         discard self.objects.pop()
     when DEBUG_TRACE_ALLOCATION:
-        echo &"Freed {objCount} objects"
+        echo &"DEBUG: Freed {objCount} objects"
 
 
 proc freeVM*(self: var VM) =
     ## Tears down the VM
     when DEBUG_TRACE_ALLOCATION:
-        echo "\nFreeing all allocated memory before exiting"
+        echo "\nDEBUG: Freeing all allocated memory before exiting"
     unsetControlCHook()
     try:
         self.freeObjects()